RNZ's three-month investigation into Auckland's black-market tobacco trade has revealed alarming levels of toxic metals in illicit cigarettes. Lab testing at the University of Auckland compared three samples: legitimate Chesterfield Blue cigarettes and two black-market brands, Double Happiness and Hongtashan 1956. Professor David Barker found Double Happiness contained high levels of tin, indium, caesium, and uranium—90.8 micrograms per litre, more than double the other samples combined. The Hongtashan cigarettes had roughly 40 percent more lead than legal smokes (1013 micrograms per litre compared to 722) and both black-market brands contained cadmium levels up to 60 percent higher than the legitimate counterpart.